Write 'True' or 'False' and justify your answer:
Two identical solid hemispheres of equal base radius $r \text{ cm}$ are joined together along their bases. The total surface area of the resulting solid is $6 \pi r^{2}$.

The base of a cone with radius $7\, cm$ and height $24\, cm$ is hemispherical. Find the cost of painting its surface at the rate of ₹ $2/cm^2$. (in ₹)

Total surface area of a cube open at one end $= \dots$

$A$ wooden article was made by scooping out a hemisphere from each end of a solid cylinder,as shown in the figure. If the height of the cylinder is $10 \, cm$ and its base radius is $3.5 \, cm$,find the total surface area of the article (in $cm^2$).

The $CSA$ of a cone with radius $4 \, cm$ and slant height $6 \, cm$ is $\ldots \ldots \ldots \ldots cm^{2}$. (in $\pi$)

$2$ cubes each of volume $64 \, cm^3$ are joined end to end. Find the surface area of the resulting cuboid in $cm^2$.